1. Field of The Invention
The present invention relates to the field of automatic processing machinery used in the packaging industry. More particularly, the present invention relates to the field of automatic carton feeder apparatus for individually removing a flat carton blank from a magazine which retains a multiplicity of carton blanks in collapsed condition, partially or fully opening the carton blank, and depositing the carton blank on a conveyor assembly in the opened condition so that it is ready to receive goods as it moves along the conveyor assembly.
2. Description of The Prior Art
In general, automatic machinery which automates operations previously performed by manual labor is known in the prior art. In addition, machinery which is placed on a carousel and caused to rotate in the clockwise or counterclockwise direction while causing operating components on the machine to move from station to station and performing one or more tasks is generally known in the prior art. Furthermore, operating components such as gear and sprocket assemblies which cause the rotation of the carousel and also the rotation of one or more operating stations on the carousel, and pneumatic air valve or cam and cam follower assemblies which cause rods to move back and forth are generally known in the prior art. Finally, assemblies such as pneumatic suction cups are also well known in the prior art.
While there have been some machines known in the prior art which are designed to perform automatic carton opening and feeding operations, they either did not perform satisfactorily in actual operation, or were too complicated. The following prior art patents are related to the pertinent field.
1. U.S. Pat. No. 2,601,148 issued to Williams on Jun. 24, 1952 for "Means For Opening And Loading Carton Blanks" (hereafter "the Williams Patent").
2. U.S. Pat. No. 2,936,861 issued to Earp on May 17, 1960 for "Container Blank Feeder Mechanism" (hereafter "the Earp Patent").
3. U.S. Pat. No. 3,242,827 issued to Winters on Mar. 29, 1966 for "Apparatus And Method For Opening Cartons" (hereafter "the Winters Patent").
4. U.S. Pat. No. 3,599,541 issued to Allen on Aug. 17, 1971 for "Container Blank Variable-Speed Feeder Apparatus" (hereafter "the Allen Patent").
5. U.S. Pat. No. 4,194,442 issued to Martelli on Mar. 25, 1980 for Device For Picking Up Semi-Rigid Sheet-Like Elements From A Magazine And Transferring Them Onto A Conveyor" (hereafter "the Martelli Patent").
6. U.S. Pat. No. 4,537,587 issued to Langen on Aug. 27, 1985 for "Carton Opening Mechanism" (hereafter "the Langen Patent").
7. U.S. Pat. No. 4,596,545 issued to Greenwell on Jun. 24, 1986 for "Orbital Feeder" (hereafter "the Greenwell Patent").
The Greenwell Patent discloses an apparatus for feeding flat folded cartons from a stationary magazine to a continuously moving conveyor. A plurality of planar members with attached suction cups are rotatably mounted on a rotary carrier. A fixed cam cooperates with cam followers mounted on the planetary members to cause the planetary members to rotate on their own axis as the carrier rotates to pick up cartons from the magazine, open them and deposit them gently between transport lugs on the conveyor.
The Langen Patent discloses a carton opening mechanism for use in opening knocked-down cartons. The carton opening mechanism has a first suction face which is circumferentially spaced 120 degrees from the discharging opening of a magazine. A rotary transfer mechanism has a suction head formed with a second suction face. The carton is held between the first and second suction faces and caused to be opened while being transferred.
The Martelli Patent discloses a device for picking up carton blanks from a magazine and transferring them to a conveyor. The device has a rotating body supported by a horizontal and fixed shaft supporting a radial cam and an arm which is oscillating in a plane normal to the shaft and serving as a radial guide for a gripping member.
The Allen Patent discloses a container blank feeder apparatus for feeding containers in a collapsed form from a container magazine to a feeding station on a machine for erecting the containers for forming and filling operations. The feeder apparatus includes a base, a rotatable turret mounted on the base, and a plurality of suction cups movably mounted for rotation about the turret and for radial movements for gripping and removing the collapsed container blanks from the magazine and conveying them to the feeding station.
The Winters Patent discloses a turret-type feeder assembly for opening cartons. The feeder assembly includes a rotary bowl assembly and several pairs of suction cups. Each pair of suction cups includes an inboard suction cup for picking up a carton blank from its front panel, and an outboard suction cup for gripping the carton blank from its back panel and causing the carton blank to be opened.
The Earp Patent discloses an early container blank feeder mechanism. The feeder mechanism includes suction devices which moves radially from a turret rotating continuously at a constant angular speed to engage a container blank and remove it from a magazine. The container blank is then transferred to and deposited on a conveyor.
The Williams Patent discloses another earlier container blank opening and loading mechanism. The opening and loading mechanism includes a suction cup for holding and transporting a container blank, and a pivot claw for opening the carton when it is engaged with a fin on a rotary conveyor.
One of the difficulties encountered by the automatic carton opening and feeding machinery is how to effectively open the carton blank. Referring to FIG. 1, there is shown a typical carton blank 300. Carton blank 300 has a front panel 302, a rear panel 304, two opposite side panels 306, and several top and bottom flaps 308. The various panels of the carton blank 300 are connected along their adjacent edges. However, to facilitate opening and forming of the carton blank 300, it has been pre-folded or broken along the adjacent edges. These pre-folded or broken edges are known as "breaking score lines" or simply "scores" in the industry. For example, the scoring line between the front panel 302 and one side panel 306 is line 310. When the carton blank 300 is just removed from a magazine, it is in its essentially folded or collapsed condition. When the carton blank 300 is to be deposited to a conveyor, however, it is supposed to be in its essentially folded or collapsed condition. Therefore, to open at least partially the carton blank 300 is one of the basic tasks an automatic carton feeding machine needs to perform.
The prior art automatic carton opening and feeding assemblies have utilized several different types of approaches to achieve the objective of causing the carton blanks to open while being transferred from the magazine to the conveyor. One earlier approach is to utilize stationary angled abutment members. The Earp Patent is an example of this type of approach. Referring to FIG. 12 of the Earp Patent, a stationary angled abutment member is mounted at a fixed location along the transferring path of the carton blanks. As a carton blank is held by a suction cup at its front panel and moving along the transferring path, its one side panel engages with the stationary angled abutment member, which breaks the carton and causes it to be partially opened. The Allen Patent also utilizes a similar stationary angled abutment member to break open the carton blank (see FIG. 16 of the Allen Patent). A disadvantage of this type of approach is that the angled abutment members have to be mounted at some fixed locations adjacent to the rotary bases of the carton opening and feeding assemblies.
The Williams Patent discloses another early approach of the opening mechanism. The Williams Patent utilizes a revolving claw which is mounted at a fixed location adjacent to where the carton blank is to be deposited onto a conveyor. Referring to FIG. 3 of the Williams Patent, when the carton blank is carried by a suction cap and ready to be deposited to the conveyor, one of the spaced fins on the conveyor is engaged with one of the score lines of the carton blank, and the revolving claw is engaged with an opposite score line of the carton blank and causes the carton blank to be opened. A disadvantage of this type of approach is that it includes a complicated claw mechanism which is a separate part of the rotary work-station of the suction cup.
A different type of approach of the opening mechanism is to utilize additional opposite side suction cups. The Winters Patent teaches the use of opposite side suction cups. The carton blank is held by a front suction cup which engages its front panel and is opened by an additional suction cup which engages its back panel. The Langen Patent (FIG. 4) and the Martelli Patent (FIG. 1) also teach the use of additional suction cups engaged at different panels of the carton blank for causing the carton blank to be opened. A disadvantage of this type of approach is that the use of additional separate suction cups makes the carton opening and feeding assemblies more complicated and increases the cost of manufacture and maintenance.
The Greenwell Patent discloses still another approach of the opening mechanism. Referring to FIG. 2 of the Greenwell Patent, there is shown a small channel-shaped element mounted behind the suction cup. When the suction cup moves backward with a carton blank, the small channel-shaped element will engage two adjacent panels of the carton blank and cause it to be partially opened. A disadvantage of this type of approach is that in order to have the small channel-shaped element engaged with two adjacent panels of the carton blank, the suction cup has to engage the carton blank at a location on or about the score line between the two adjacent panels, which reduces the affixing effect of the suction cup since it works better when it engages on a flat surface.
The inventor and applicant of the instant application, Boris Bershadsky, is also the inventor and patentee of U.S. Pat. No. 5,049,119 issued on Sep. 17, 1991 (hereafter "the '119 Patent"), which disclosed an apparatus for removing a flat carton from a magazine, causing the carton to open, and placing the carton in a conveyor assembly. The '119 Patent has disclosed a novel approach of the opening mechanism. Referring to FIG. 5 of the '119 Patent, two fixed spaced apart transverse members (denoted by numerals 102 and 103) are positioned in parallel to the moving direction of the suction cup. When the carton blank comes in contact with both or at least one of the two fixed spaced apart transverse members, it is at least partially opened by the impact of the contact. Due to this distance between the two fixed spaced apart transverse members, this arrangement allows the suction cup to attach to the flat front panel of the carton blank, and makes the attachment more secure.
The automatic carton opening and feeding apparatus disclosed by the '119 Patent performs well in most of the situations. Nevertheless it has been experienced that for large sized carton blanks, sometimes the opening mechanism is not as effective as for medium and small sized carton blanks. Large carton blanks sometimes cannot be effectively opened or become tilted or even get knocked off when they come into contact with the fixed spaced apart transverse members mounted behind the suction cup. Therefore, it is highly desirable to improve the automatic carton opening and feeding apparatus so that the system performs satisfactorily with not only small and medium sized carton blanks, but also large sized carton blanks.